Who's "we?"

So this lady I know was having a conversation with me and she lamented that "we" were soon going to be in the minority.  I was a little shocked that she was telling me this and I asked her, "who's 'we?'"  She pinched her skin, "you know, white people."

...I'm not white.

Sometimes I just have to wonder what it is about me that makes people think I am white.  She isn't the only one.  My friend Sara once said that she thinks of me as being white.  My dad has flat out told me I was white.  I suppose the answer came from one of my sister's professors who would probably label me an acculturated white.  I'm pretty sure I've mentioned that before and how offended I was.